Automatic boiler water conditioner and blow-off system



AUTOMATIC BOILER WATER CONDITIONER AND BLOW-OFF SYSTEM L. o. GUNDERSON El AL Filed 001:. 9, 1956 2 Sheets-Sheet l Garzdqsvm OZand' W Cara-m Zew Oct. 4, 1938. o. GUNDERSON ET AL 2,132,028.

AUTOMATIC BOILER WATER CONDITIONER AND BLOW-OFF SYSTEM Filed Oct. 9, 1956 2 Sheets-Sheet 2 -ZZ7VE[72L7R5 0. 6mm wand Iv. (av-rick Patented Oct. .4, 1938 UNITED STATES AUTOMATIC BOILER. WATER CONDITIONER AND BLOW-OFF SYSTEM Lewis 0. Gunderson and Oland w. Garrick, cmcago, Ill., assignors to Electro-Chemical Engineering Corporation, Chicago, 111.. a corporation "of Delaware -Application October 9, 1936, Serial No. 104,760

23 Claims.

This invention relates to the collecting and discharging of collapsed foam from the upper portion of a steam boiler to remove foam forming and foam stabilizing ingredients that have been adsorbed and accumulated in the water surface and foam bubble More specifically, this invention relates to apparatus for discharging the water from collected collapsed foam in a boiler without waste of steam from the boiler while simultaneously actuating a blow-off valve for intermittently removing sludge and sediment from the boiler. V

In the Carrick and Seniii U; S. Patent No. 2,038,414 dated April 21, 1936, there is described and claimed a'foam indicating and control apparatus for steam boilers wherein the moisture entrainment in the steam above the boiler water is accurately indicated while the-steam is still in the boiler by means of a collecting tube disposed in the steam space of the boiler for sampling the moisture in the steam. The collected moisture is drained through an indicating means and can actuate a blow-ofi mechanismfor blowing down the boiler. However in this patent the boiler is blown off in the usual manner from the lower portions thereof.

We have found that the foam forming ingredients and foam stabilizing ingredients in boiler water accumulate or are positively adsorbed in the steam .bubble interfaces or in the'foam films.

As these substances are released at the water surface upon breaking of the steam bubbles it is apparent that they are free to recirculate in the boiler water, repeating their function of bringing about foam formation and stabilization by be coming adsorbed in the surfaces of new steam stabilizing ingredients is collected at the top level of the boiler water and'discharged from the boiler. The apparatus of this invention provides for the removal of the concentrated boiler water f containing the foam producing and foam stabilizing substances without discharging substantial amounts of steam from the boiler and therefore difi'ers widely from previously used skimmers which consisted of perforated pipes located at the surface of the boiler water to skimofl foam therefrom. These skimmers,-however, permitted the These substances therefore perpetuate discharge of large amounts of steam and were very ineflicient for blowing down the boiler to remove foam producing substances.

It is then an object of this invention to provideapparatus for removing foam producing and foam stabilizing ingredients from steam boilers in operation. i

A further object of this invention is to provide apparatus for collecting collapsed foam or light water at the boiler water surface in an operating steam boiler and discharge this materialwithout discharge of substantial amounts of steam from the boiler.

A further object of this invention is to provide an automatic blow-off apparatus for steam boilers actuated by water containing large amounts of foam forming and foam stabilizing ingredients that have been collected from the boiler water.

A further object of this invention is to discharge from an operating steam boiler, the water from collapsed foam collected near the upper portion of the boiler together with sludge and sedielevational view, with a part broken away and shown in cross section, of a locomotive boiler showing our invention applied thereto.

Figure 2 is a diagrammatic vertical cross-sectional view taken substantially along the line 11-11 of Figure. 1.

Figure 3 is an enlarged elevational view of the blow-off valve illustrated in the lower right-hand corner ofF'1gure 1.

Figure 4 is a fragmentary diagrammatic view with a part broken away and shown in cross section, of a locomotive boiler showing a modified form of our invention applied thereto.

Figure 5 is an enlarged fragmentary vertical cross-sectional view taken substantially along the line .V-V of Figure 4.

Figure 6 is an elevational view of an alternative form of pipe line system for the apparatus shown in Figure 4.

' Figure '7 is an enlarged vertical cross-sectional view of the blow-01f valve illustrated in the lower right-hand corner ofFigure 4.

As shown on the drawings: 1 The invention is shown as applied to a locomotive boiler but it should be understood that the invention may be applied, as well, to other of boilers. The locomotive boiler l0 shown in Figures 1 and 2 comprises the usual boiler shell II and a fire box l2 defined by the sheet I3. Boiler tubes l4 extend in communication with the fire box forwardly through the sheet l3.

Under usual operating conditions water I! surrounds the tubes l4 and the fire box l2 and ex-'- tends upwardly to the normal water line I6 which is a slight distance above the crown sheet II for the fire box.

. The space I!) between the water level l6 and the top of the boiler is the steam space of the boiler from which steam is supplied to the steam dome 20 for feeding the operating cylinders (not shown) of the locomotive.

According to this invention a collecting basin 2| is located approximately at the normal 'water level l6 in the boiler and the bottom of the basin may be slightly below or slightly elevated from that level as long as the top edges of the basin are above the normal water level. The basin 2| is suspended from the boiler shell II by means of straps 22 and 23 and is thus held rigidly in the boiler and extends transversely thereacross without interfering with the flow of steam to the steam dome 20. The basin 2| is preferably located, as shown in Figure 1, between the steam dome '20 and the primary evaporation zone of the boiler so that it will intercept any excessive foam development in the boiler that might otherwise continue toward the steam outlet in the steam dome and be entrained with the steam.

'When the boiler is in operation the buoyancy of' the steam bubbles increases the volume of the boiler water such that the top edge of the basin will be below the water level. A pipe 24 communicates with the bottom-of the basin 2| and with the inlet 25 of a blow-off valve 26, which may be of any usual construction. The blow-oil valve when opened will ,cause the water in the basin 2| to be drained fromthe basin and discharged from boiler through a discharge line 21 communicating with the valve 26 and with a steam separator 28 mounted on top of the boiler shell Steam and water are separated from each other in the separator 28 and the steam discharged upwardly at 29 from the separator 28.

The water is discharged through a downwardly extending pipe 30 to the road bed below the boiler as' at 3|.

If desired the blow-off valve 26 can also discharge water from the mud ring in the boiler.

For this purpose, the blow-off valve 26 is secured to a flange 32 of a pipe 33 extending through the boiler shell II as indicated in Figure 3. The

pipe 33 communicates with the mud ring of the boiler and when the valve 26 is opened, sludge and sediment will be discharged through the pipe 33 into the blow-oil valve 26' and through the discharge pipe 21 into the steam separator 28 wherethe steam is separated therefrom and the sludge water is discharged tothe road bed.

The blow-off valve 26 can be opened by steam pressure from the locomotive boiler supplied through a pipe line 34.. Admission of steam through the pipe line 34 is controlled by an operating valve 35 mounted in the cab 36 of the locomotive. When the valve 35 is opened the steam pressure of the boiler is exerted in the pipe line 34 and this pressure causes the blow-01! valve to open thereby discharging water from the basin 2| and sludge and. sediment from the mud ring of the boiler.

The amount of discharge through the blow-off valve 26 from the basin 2| or from the mud ring may be controlled by the size of the pipes 24 and 33 or by placing regulating valves such as 24a in either or both of these pipes. A shut-off valve 31 may be provided in the blow-off valve 26'to permit disassembly of the blow-off valve for repair purposes without removing pressure from the boiler. v

' It should be understood that any type of blowoff valve can be used.

From the above description of Figures. 1 to 3, it should be understood that the foam stabilizing and foam producing substances are concentrated at the top water level in the boiler in what clS known as concentrated water or light water. This light water is collected in the basin 2| and is discharged from the boiler thereby removing the foam producing and foam stabilizing materials. Since. the collecting basin is drained from' the bottom thereof, there -is no material loss of steam when the boiler is blown down.

In accordance with this invention sludge and sediment can also be blown from the boiler simultaneously with the removal of concentrated boiler water.

Steam is separated from the discharged concentrated boiler water and the discharged sludge water and released to the atmosphere above the boiler. The sludge water and the concentrated water are discharged with harmless force to the road bed below the locomotive.

In Figures 4 and 5 parts identical with parts described in Figures 1 and 2 have been designated by the same reference numerals.

In Figures 4 and 5, the reference numerals 40 and 4| designateseparate buckets or basins having open tops and closed bottoms mounted in the steam space IQ of the boiler with their bottoms extending into the boiler water |5 below the normal level l6 thereof. The bucket 4| is taller than the bucket 46 and extends thereabove as shown.

Brackets '42 and 43 support the buckets 40 and 4| from the boiler shell The position of the buckets with respect to the boiler water |5 can be adjusted such as,.for example, byproviding. slots in the straps or brackets 42 and 43.

Pipes 44 and 45 enter through the boiler shell II as best shown in Figure 5 and extend hOl'lZOD-e tally through the steam space IQ of the boiler into the buckets 4ll-and 4| respectively. The pipes 44 and. 45 are bent downwardly in the centers of the buckets to form siphon legs 44a and 45a respectively. The siphon legs 44a and 45a terminate near the bottoms of the buckets or basins 40 and 4|. By arranging the tops of the buckets at two different levels in the boiler, the lower bucket 40 will collect collapsed foam before the foam level in the boiler reaches'the level of the top of bucket 4 I. The matter collected in bucket 40 is discharged from below its surface by the siphon leg 4411 into the pipe 44 whenever its level in the bucket is is discharged therefrom from below its surface into the pipe 45 by the siphon'leg 45a.

The pipe 45, outside of the boiler shell feeds into a valve 46 of the steam trap type mounted on the boiler near the bottom thereof as best shown in Figure}. The valve 46 discharges into a horizontal pipe 41 extending toward the rear' of the boiler.

' The pipe 44, outside of the boiler shell ll, 75

, from the inlet portion 54 into the discharge terminates in a valve 48 of the steam trap type mounted on the boiler near the bottom thereof. The valves and 48 are adapted to be opened by water collected therein but are not opened by steam. The valve 48 dischargesthrough a pipe 49 into the pipe 41.

The siphon legs 44a and 45a prevent spasmodic operation of the steam traps 46 and 48 whenever a little water is splashed into the buckets 44 and 45 since water will not enter the traps until either bucket is filled above the siphon neck of the siphon legs. The traps will then operate continuously until the buckets are emptied into municates 'with the pipe line 41 ahead of the" blow-oil valve 58 and registers with apressure gauge 52 in the cab 38 of the locomotive. The pressure within the pipe line 41 is thereby indicated to the operator in the cab and indicates when the valves 45 or 48 are open and water is draining from the bucketsf The blow-off valve 58 comprises a passaged body portion 53 having an inlet 54 for connection to the'pipe 41, a sludge water inlet 55 for connection with a. pipe 56 leading from the bottom portion or mud ring of the boiler and a discharge portion 51 communicating with the pipe line 21 to the steam separator 28.

The body portion 53 is provided with an annular valve seat 58 about a port 59 that provides communication between the inlet portion 54 and the discharge 51. A piston 68 is slidably mounted in the cylindrical portion 5| above the port 59 and is adapted to seat against the annular seat 58 by virtue of pressure in the inlet portion 54 on the relatively large area of the top 5811 of the piston.

The piston 68 is provided with an upper cylindrical portion 52 that extends into a recessed plug 83 threaded into the top of the body portion 53 of the valve. The cylindrical portion 52 is provided with a condensate groove 54 to prevent water from being trapped above'the cylindrical portion 52.

The piston head 58 is also provided with a duct extending therethrough to permit drainage portion 51. s

I The piston 58 is also provided with an elon- 5 the discharge portion 51 into the sludge inlet portion 55 of the valve for a purpose to be hereinafter described.

gated reduced lower end 85 extending through The body portion 53 is provided with a threaded bore 51 between the sludge inlet 55 and dis- .plug 1|. which is threaded into the apertured lower end of the body portion 53. The plug 1| is provided with a centering boss 12 and upstanding segmental cylindrical lugs 13 that cooperate to center and position the coiled spring We have found that the boiler water at the top of the boiler contains relatively greater amounts of foam producing and'foam stabilizing substances and have therefore according to this invention collected this water in the buckets 40 and 4|. It is known that the water surface and the steam bubble interfaces of boiler water exhibit low surface tension, which means that surface active substances which produce and stabilize foam are positively adsorbed therein. This lowered surface tension induces positive adsorption of other foreign substances, both dissolved and suspended matter, particularly colloidal substances all of which accentuate the production and stabilization of foam.

The foam or steam bubbles that are collapsed in the collectingbuckets 48 and 4| will naturally contain a higher concentration of the foam producing foreign substances than the solid water withdrawn 'from the lower portions pf the boiler.

The collecting buckets are arrranged at two different levels with the bucket 48'being designed to collect foam or light water from a' level approximately even with the top reading of the water glass on a locomotive'boiler. As water accumulates in the bucket 48 and passes above the siphon neck or leg 44a it will flow into the valve 48 through the pipe line 44. The valve 48 opens to discharge water into the pipe line 41'." The water in the pipe line 41 is discharged into the blow-off valve 58 in the inlet port 54 thereof on top of the piston head 58. .Since the flow from valve- 48 will not ordinarily be sufiicient to depress the piston 58, the water from the valve flowing through the pipe line 41 passes through the duct 65 in the piston head and is discharged to the steam separator 28 on top of the boiler through the pipe line 21. Any steam is liberated to the atmosphere through the opening 29 of the separator 28 while the water is drained with harmless force to the road bed through the discharge pipe line 38.

When water has been completely discharged from the bucket 48 steam will flow through the pipe 44 into the valve 48 thereby causing this valve to close due to the absence of water. The discharge of water from the boiler is then discontinued until water is again accumulated in the bucket 48. The discharge of boiler water from the bucket 48 may be of relatively small magnitude such as three to five gallons perv bucket 40 will be so arranged that it will be insufficient to completely condition the boiler water to keep foam developments from rising above the level of the cylinder 48. Therefore periodically the foam or light water will develop above the level of foam collector 48 and will be accumulated irr'the bucket 4|. When the water in the bucket 4| reaches a level above the siphon leg 45a of the pipe line 45 it Will be discharged into the valve 46. The water will open the'valvg 45 and flow into the pipe line 41.v

The combined water streams from the valves 45 and 48 will be in excess of the amount that can be freely discharged through the duct 65 of the piston head 68 in' the blow o'fl valve 58 thus creating a pressure above the piston head in the blow-off valve and causing the piston to be seated 7 against the valve seat 58. This downward movement of the piston causes the end portion 56 thereof to depress the ball 69 thus communicating the sludge water inlet 58 with the discharge opening 51 and permitting a blowing off of the lower portion of the boiler into the pipe line 21 to the steam separator. The blowing off of the lower portion of the boiler thus prevents the accumulation of, excessive solid foreign matter in the boiler and decreases the foaming therein so that the valves 46 and 48 will be closed and the piston 60 will again rise in the blow-oil valve to shut off the flow of sludge water from the boiler. Obviously; the discharge from the valve 46 alone may, in some instances, be sufilcient to operate the blow-off valve 50 for the discharge of sludge water as, for example, when the valve 48 becomes inoperative.

It should be understood'that normally the concentrated or light water in the bucket 48 can be continually discharged without actuating the blow -ofl valve 50. However when the concentrated or light water accumulates so as to rise beyond the top portion of the siphon leg 45a in the bucket 4|, this increased flow is sufficient to open the blow-01f valve for the discharge of sludge water from the boiler thereby decreasing the foreign ingredients in the boiler water and lowering the foam. Even if no water collects in the buckets 48 and 4!, steam contained in the pipe lines 44 and 45 will eventually condense forming water to open 'the valves 46 and 48 at infrequent intervals to discharge water. This is beneficial incold weather to prevent a freeze-up of the blow-off system and assures an opening of the blow-off valve 5% at least at infrequent intervals to remove accumulated sludge.

7 It should also be understood that the blow-off system can be used without the blow-off valve Eli for discharging sludge water. In other words the collecting buckets can be used alone in connection with valves such as 46 and 48 for removing concentrated water from the boiler.

In Figure 6 there is illustrated another modification of the system wherein the pipe line 45 from the bucket 4| terminates in the valve 46 and dis charges water into the pipe line 4'! as described in Figure 4. However the discharge pipe 44 from the bucket 40 communicates with a valve 48 of the steam trap type which valve 48 discharges through a pipe 80 into a second steam separator 8| mounted at the lower portion of the boiler. Thus water from the bucket 48 is discharged sep-' arately from water from the cylinder 4!. The steam separator is provided with a steam discharge opening 82 at the top thereof and a water drain as atthe bottom thereof. In this manner some of the light or concentrated water is discharged through a separate system and the bucket 4l collects the excessive foam or light water for actuating the blow-off valve to discharge sludge water from the boiler.-

From the above description it should be understood that many modifications of the illus which operate whenever the boiler is in service.' With the systems of this invention blowing oifis not accomplished after washouts or water changes and does not take place until the boiler water concentration reaches a definite value. for example, within seventy-five percent of the maximum allowable concentration. The systems are entirely automatic and carry out the function of maintaining a uniform desirable concentration of boiler water without manual interference. systems further provide for the most eflicient removal of foam forming and foam stabilizing substances with the least waste of boiler water and thus with the least interference with the operating efliciency of the boiler.

The collection of foam forming and foam stabilizing substances in the collapsed foam films will permit the maintenance of higher concentrations of soluble mineral salts in the boiler water, thus materially reducing the waste of water blown out to prevent foaming. Since water blown out from a collapsed foam film source contains higher percentages of the foam forming substances than the main body of boiler water, the percentage of these substances in the boiler water will be materially reduced simultaneously with the increased concentration of dissolved mineral salts in the water. This results in many advantages besides saving of boiler water in that it permits the maintenance of a higher alkalinity of the boiler water without danger of excessive foaming. The maintenance of higher alkalinity reduces the corrosive qualities of the water and will increase the effectiveness of the chemical treatment of the boiler water to prevent all types of scale formation.

As pointed out above the system of this .invention utilizing basins, buckets and other collecting means for collapsed foam above the normal visible water level, intercepts the foam. simultaneously developed in the evaporation zones of the boiler and prevents its reaching the steam outlet.

We are aware that many changes may be made and numerous details of construction may be varied through a wide range without departing from the principles .of this invention, and we therefore, do not purpose limiting the patent granted hereon otherwise than necessitated by the prior art. 7 1

We claim as our invention:

l. The method of controlling boiler water in operating steam boilers which comprises collecting water directly from the main body of light boiler water only above the normal level of water in the boiler and periodically draining the collected water from the boiler without substantial discharge of steam therewith.

2. The method of controlling foaming of boiler water in operating steam boilers which comprises collecting directly from the main body of water in the boiler; only water from collapsed foam on top of the boiler water and periodically discharging the collected water from the boiler without substantial discharge of steam therewith.

3. The method of controlling foaming of boiler water in operating steam boilers which comprises segregating directly from the main body of water in the boiler, only water from collapsed foam on s top of the boiler water, and dischargingthe segregated water from the boiler when a predetermined amount has been segregated without venting the steam space of the boiler to the atmos- 7 phere.

The.

the steam space of the boiler to the atmosphere and simultaneously blowing off sludge water from the bottom of the boiler.

5. The method of controlling foaming in operating steam boilers which comprises segregating directly from the main body of water in the boiler, only concentrated boiler water from collapsed foam on top of the boiler water, periodicallydischarging the segregated water from the boiler from below the surface of said water to, prevent discharge of steam therewith and simultaneously blowing off sludge water from the bottom of the boiler.

6. The method of controlling foaming in operating steam boilers which comprises collecting directly from the main body of water in the boiler, only water from collapsed foam on top of the boiler water, flowing the collected water from below the surface thereof out of the boiler to prevent discharge of steam with the water and blowing ofl sludge water from the bottom of the boiler whenever the flow of concentrated water increases beyond a predetermined amount.

7. The method of controlling foaming in operating steam boilers with least possible waste of boiler water which comprises collecting directly from the main body of water in the boiler, only water from collapsed foam on top of the boiler water in the steam space of the boiler, flowing the collected water out of the boiler without substantial discharge of steam therewith and utilizing the flowing water to blow off sludge water from the bottom of the boiler whenever the flow increases beyond a predetermined rate.

8. The method of operating locomotive boilers to control foaming of boiler water therein which comprises collecting concentrated water from collapsed foam on" top of the boiler water directly from the main body of water in the boiler in the steam space of the boiler, draining the collected concentrated water through a steam trap from below the level thereof out of the boiler to prevent discharge of steam therewith, flowing the dra ned water into a blow-off valve and actuating said valve with the flow of water to blow oif sludge water from the bottom of the boiler.

9. Apparatus for controlling foaming in operating steam boilers comprising a pair of open topped buckets vertically mounted in the steam space of the boiler than the top of the other bucket, indi-' vidual pipe lines extending from outside of the boiler into the buckets and having downwardly turned leg portions terminating in the buckets, near the bottoms thereof. steam traps, each at a level beneath the buckets, communicating with said pipe lines for receiving water and steam from the buckets. a discharge line communicating with the steam traps for-receiving water therefrom, a water actuated blow-off valve communicating with said discharge line having a restricted passageway accommodating limited flow of water from said line therethrough, said valve being opened by an increased flow of water therein from said line, a sludge pipe communicating with the lower portion of the boiler and with the blow-ofl' valve, and a drain line from said blow-off valve.

10. Apparatus for controlling foaming in steamboilers with least possible waste of boiler water which comprises means for collecting water from collapsed foam at separate levels in the boiler within the light water zone thereof, pipe lines for draining the collected water from the boiler, steam traps below the water collecting means in said pipe lines preventing the passage of steam therethrough, a blow-on valve, a discharge line communicating with said steam traps and with said blow-off valve, a sludge discharge pipe comihunicating with the valve and with the lower portion of the-boiler, means in said valve actuated by flow of water from the steam traps discharge line into the valve for opening and closing the sludge blow-ofi and a drain line from said blowoff valve for receiving the sludge water and the collected water therefrom) V 11. Apparatus for controllingfoaming in operating steam boilers which comprises a collecting means mounted in the boiler in communication with the boiler only above the normal water level.

directly from the main body of water in the boiler,

a pipe line communicating with the lower portion of said means to drain the means, a blow-off valve outside of the boiler communicating with said pipe line, means communicating the blow-off valve with the lower portion ofthe boiler, and means a responsive to periodic liquid flow through the pipe line for actuating said blow-off valve to discharge water from the collectingmeans and sludge water from the boiler.

12. Apparatus for controlling foaming in operating steam boilers which comprises an open topped bucket vertically mounted in the steam space of a boiler with the lower end thereof below the normal level of water in the boiler and the open top in communication with the light water zone in the boiler. a pipe line extending'into the bucket from outside of the boiler and having a downturned leg portion terminating near the bottom of the bucket. a steam trap outside of the boiler below the bucket communicating with the pipe line. said trap being actuated whenever water collected in the bucket overflows the leg portion of the pipe thereby discharging water into the trap until the bucket is emntid below said leg and a discharge line for receiving water from the steam 13. Apparatus for controlling foaming in operating steam boilers comprising a pair of buckets vertically mounted in the steam s ace of a boiler in communication with the boiler at separate levels above normal water level in the boiler for receiving therein light water formed on top of the boiler water, individual pipe lines extending having downwardly turned leg portions terminating in the buckets near the bottoms thereof, steam traps outside of the boiler below the levels of the buckets communicating with said pipe lines for receiving water and steam from the buckets, a discharge line communicating with the steam traps for receiving water therefrom, a water actuated blow-off valve communicating with said discharge line having a passage accommodating a limited flow of water from said line therethrough and means to open the valve actuated by flow of water'from said line whenever saidflow exceeds said limited amount accommodated by said passage, a sludge pipe communicating with the lower portion of the boiler and with the blow-ofl' valve, and a. drain l ne from said blow-61f valve for receiving the water from the steam traps and the sludge water from the blow-ofl valve.

14. The method of controlling foaming in steam boilers with the least possible waste of boiler water which comprises collecting in a container directly from the main body of boiler water in the steam space of the boiler, concentrated water from collapsed team on top of the boiler water.

50 from outside of the boiler into said buckets and draining the collected water out of theboiler and periodically discharging said water only without.

discharge of steam therewith until said container 'is substantially empty.

15. The method of controlling-foaming in steam boilers with the least possible waste of boiler water which comprises collecting in a container concentrated water from collapsed foam on top of the boiler water in the steam space of the boiler directly from the main body of water in the boiler,

draining the collected water out of the boiler,

discharging the water only without substantial discharge of steam therewith, utilizing said water to actuate a blowing off of sludge water from the boiler and discharging said sludge water coinci dentally with the discharge of water-from said water responsive valve. 1

16. Apparatus for controlling foaming in oper-- ating steam boilers which comprises water collecting means in the boiler having the inlet thereof above the normal water level in the boiler but below the steam outlet, said inlet being in communication only with the main body of light boiler water formed on top of the boiler water for directly receiving light water into thecollecting means, a drain line for draining liquid from the collecting means and a liquid responsive valve in said drain line below the collecting means for effecting periodic discharge ofliquid from the collecting means, said valve being so constructed and arranged to open upon a predetermined flow of liquid thereto and close upon cessation of said flow.

17. Apparatus for controlling foaming in operating steam boilers which comprises water collecting means in the boiler having the inlet thereof above the normal water level in the boiler but below the steam outlet, said inlet being in communication with the main body'of light boiler water formed on top of the boiler water for directly receiving light water into the collecting means, a drain line extending into the collecting means having a downturned leg portion terminating near the bottom of the collecting means and a liquid responsive valve in said drain line at a level below the collecting means, said valve'being so constructed and arranged to open upon a predetermined fiow of liquid thereto and close upon a cessation of said flow whereby a rise in liquid level in the collecting means above the downturned leg portion therein effects a siphoning of liquid out of the collecting means into the valve to open the valve for discharge of liquid until the liquid level in the collecting means is below the leg portion whereupon the liquid flow to the valve ceases and the valve closes to prevent discharge of steam. I

18. The method of controlling foaming in operating steam boilers which comprises collecting directly from the main body of water in the boiler only the light water formed above the normal level of waterin the boiler, periodically siphoning the collected water whenever the same exceeds a predetermined level and discharging said water with-- out venting steam in the steam space to the atmosphere.

- l9. Apparatus for removiiig foam producing and operating steam boilers which comprises means in the upper. portion of the boiler so positioned as to collect directly from the main body of water in the boiler, only light water and water from col lapsed foam on the boiler water, a drain pipe communicating with the lower portion of said means to remove collected water therefrom, and a valve in said pipe for controlling the flow of water therethrough. I

20. Apparatus for controlling foaming in oper:

ating steam boilers which comprises an opentopped bucket vertically mounted in the steam space of the boiler with the lower end thereof below the normal level of water in the boiler, a pipe extending into the buckehfrom outside of the boiler and having a downturned leg portion terminating in the bucket near the bottom thereof, said leg portion being vented at the top thereof, a steam trap at a level below the bucket comtherein, steam traps below the level of the collecting means communicating with each of said pipes, a discharge line communicating with the steam traps to receive water therefrom, a blowoir valve casing in communication with the lower portion of the boiler, a piston slidable in said valve casing, means in the valve casing operated by the piston to open and close the valve, said discharge line terminating in said valve casing above the piston therein to feed water from the traps to the piston for operating the piston and a. duct in said piston allowing drainage of a predetermined flow of water from the discharge line, said blow-oi! valve parts being so constructed and arranged that a flow greater than a predetermined flow will depress thepiston to openthe valve and blow oflf the boiler.

22. Apparatus for controlling foaming in operating steam boilers which comprises is collecting means mounted in the boiler between the steam outlet and main evaporation zone of the boiler in direct communication with the light boiler water above the normal water level therein and posi-' tioned to collect only light water and foam generated in the boiler that might otherwise continue toward the steam outlet and be entrained in the steam delivered from the boiler, a pipe line communicating with the lower portion of said means to drain the means and a liquid responsive valve in said pipe line below the collecting means for effecting periodic discharge of the collected material.

231 The method of controlling foaming in oper-,

ating steam boilers which comprises collecting foam-generated in the boiler directly from the main body of water in the boiler only at 'a level above the normal water level in the boiler and at a point between the steam outlet and main evaporation zone of the boiler to prevent entrainment of foam and moisture in the steam issuing'from the boiler and periodically draining the collected foam from the boiler without venting steam in the steam space to the atmosphere. 

